<!DOCTYPE html>
<html>

<head>
    <meta http-equiv="Content-Type" content="text/html;charset=utf-8">
    <meta name="viewport" content="width=device-width">
    <title>MathJax</title>
    <script type="text/x-mathjax-config">
        MathJax.Hub.Config({
          tex2jax: {inlineMath: [['$','$']]}
        });
    </script>
    <script type="text/javascript" async
        src="https://cdn.bootcss.com/mathjax/2.7.5/latest.js?config=TeX-MML-AM_CHTML" async>
        </script>
    <script>
        function show() {
            document.getElementById('math').style.display = 'block';
        }
    </script>
</head>

<body>
    <p>
        <button onclick="show()">显示答案</button>
    </p>
    <p>
        <label> TITLE_TO_REPLACE </label>
    </p>


    <p id="math" style="display:none">
        MATH_FORMULA_TO_REPLACE
    </p>
</body>

</html>